Help Finding the Tension between 2 Masses

Three blocks on a frictionless surface are connected by massless strings, with M1 = 1.10 kg, M2 = 2.80 kg, and M3 = 3.50 kg. Due to the force F acting on M3, as shown, the system accelerates to the right. Given that T1 is 2.90 N, calculate T2.

I found the acceleration of the problem using F1 = m1 (T1 / (M1 + M2)). Where do I go from here?